Derivative Instruments and Hedge Activities - Summary of Derivative Financial Instruments and Classification on Consolidated Statements of Financial Condition (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Derivatives Fair Value [Line Items]
Notional Amount	$ 382,352,000	$ 341,358,000
Other Assets	19,066,000	7,960,000
Other Liabilities	20,359,000	8,519,000
Other Interest Rate Derivatives
Derivatives Fair Value [Line Items]
Notional Amount	373,266,000
Other Assets	19,066,000
Other Liabilities	20,335,000
Derivatives Designated as Hedging Instruments | Interest Rate Swaps | Cash Flow Hedges
Derivatives Fair Value [Line Items]
Notional Amount	0	0
Derivatives Not Designated As Hedging Instruments | Other Credit Derivatives
Derivatives Fair Value [Line Items]
Notional Amount	9,086,000	9,302,000
Other Liabilities	24,000	12,000
Derivatives Not Designated As Hedging Instruments | Other Interest Rate Derivatives
Derivatives Fair Value [Line Items]
Notional Amount	373,266,000	332,056,000
Other Assets	19,066,000	7,960,000
Other Liabilities	$ 20,335,000	$ 8,507,000